A state police SWAT team member readies a robot to enter a home where a man had barricaded himself on Friday in Trenton, N.J. / Scott Ketterer, AP

by Katharine Lackey, USA TODAY

by Katharine Lackey, USA TODAY

A 37-hour standoff with an armed man inside a Trenton, N.J., home has ended and three children taken hostage are safe after police discovered the bodies of a woman and a 13-year-old boy.

Authorities found the bodies of Carmelita Stevens, 44, and her son in an "advanced state of decomposition," Trenton Police Director Ralph Rivera told reporters Sunday at a news conference.

Officers stormed the home early Sunday morning, wounding Gerald Tyrone Murphy, 38, with a gunshot as he threatened one of the children. Murphy was taken into custody but later died of his injuries.

The three children - two girls ages 16 and 18 and a boy, 4 - were rescued and taken to a medical center for evaluation and treatment, Mercer County Prosecutor Joseph Bocchini told reporters.

Murphy, who had been dating Stevens, was not the father of any of her children, police said.

Col. Joseph Fuentes said there was a "deteriorating state of mind" with the subject and threats to harm children during the complex standoff. Hostage negotiators were in contact with Murphy throughout the ordeal.

The hostage situation began Friday afternoon, when Trenton police were called to check on the welfare of Stevens, whose family had not heard from her in some time, Rivera said. In addition, police were told Stevens' two daughters had not been to school in 12 days.

When officers entered the home, they smelled an odor consistent with a decomposing body and found Murphy upstairs in a room.

Murphy told officers he had three children and a decomposing body in the room and that he was armed with a gun and explosives. Murphy also told officers about another body in a rear bedroom.

A man, 19, was found unharmed Friday in the basement and may have been hiding from the suspect. He was evaluated and is safely back with his family, Bocchini said. The teen said he had not seen his mother or sisters since April 24.

Bocchini said authorities believe Stevens' and her son's deaths occurred about two weeks ago.

Police say Murphy had an extensive criminal record. An arrest warrant had been issued from Pennsylvania for Murphy for failing to register as a sex offender. He had been previously arrested for robbery, weapons offenses and child endangerment.

Bocchini said there are allegations that the two teenage girls were abused and assaulted during the time they were held hostage.

Police wouldn't speculate on a motive or disclose how the two victims died.